Objective: A prospective randomized control study investigated the feasibility and efficacy of adjuvant radiotherapy on patients with central hepatocellular carcinoma (HCC) after narrow-margin hepatectomy (<1 cm). This study presents an updated 10-year real-world evidence to further characterize the role of adjuvant radiotherapy. Methods: Patients with central HCC after narrow-margin hepatectomy (<1 cm) were prospectively assigned to adjuvant radiotherapy group and control group. Patients' outcome, adverse events, long-term recurrence and survival rates were investigated. Results: The 1-, 5-, and 10-year recurrence-free survival (RFS) rates were 81.0%, 43.9%, and 38.7%, respectively in adjuvant radiotherapy group and 71.7%, 35.8%, and 24.2%, respectively in control group (log-rank test, P=0.09). The 1-, 5-, and 10-year overall survival (OS) rates were 96.6%, 54.7%, and 42.8%, respectively in adjuvant radiotherapy group and 90.2%, 55.1%, and 30.0%, respectively in control group (log-rank test, P=0.20). The 1-, 5-, and 10-year RFS rates for patients with small HCC (<= 5 cm) were 91.1%, 51.6%, and 48.4%, respectively in adjuvant radiotherapy group and 80.0%, 36.6%, and 26.6%, respectively in control group (log-rank test, P=0.03). Landmark analysis demonstrated that patients with small HCC in adjuvant radiotherapy group had a significantly improved OS in second five years after treatment in comparison to patients in control group (log-rank test, P=0.05). Conclusions: Our updated results showed a sustained clinical benefit on reducing recurrence, improving long-term survival for small central HCC by adjuvant radiotherapy after narrow-margin hepatectomy. Long-term survival data also indicated that hepatectomy is an optimal treatment for selected patients with central HCC.